Subject: [AVTCORE] draft-ietf-avtcore-srtp-aes-gcm-15

From: "Igoe, Kevin M." <[email-masked]>
Date: Tue, 14 Apr 2015 14:34:32 +0000

A new interim draft draft-ietf-avtcore-srtp-aes-gcm-15 has been posted.  This has (I hope) expunged any
references to AES-GCM and reduced to only 3 modes of AES-GCM.  The final draft will include test vectors.

I'm being cautious in the generation of test vectors (with intermediate values displayed) becuse , you REALLY 
don't want any typo's or other errors in test vectors.

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From: Magnus Westerlund <[email-masked]>
Date: Wed, 15 Apr 2015 11:12:55 +0200

> don't want any typo's or other errors in test vectors.

Hi,

Good that you posted this interim version as it allowed me to spot some
things I thing you should change.

1. Renaming the profile ID: AEAD_AES_128_GCM_8 to AEAD_AES_128_GCM_64

It looks strange to combine bits and octets for different fields.

2. Section 10, first pragraph:

s/fasmily/family

3. Section 13.2: Table 5:

Is the "(GCM)" needed now when there is only GCM in the draft?

4. Section 13.2:

Re-reading this section I wonder if it needs to be a bit more explicit
about actions. What I have understand a successful forgery will work
towards revealing the key. Thus, isn't it reasonable to actually demand
that a receiver logs how many failed forgery attempts that it has seen
and when that is sufficiently many that the security may start to be
compromised, request termination of the session. As this is a potential
Denial of service the number of attempts should be set as high as
possible to balance the risk of forgery against DoS the session.

Cheers

Magnus Westerlund

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From: "Ben Campbell" <[email-masked]>
Date: Thu, 16 Apr 2015 14:47:56 -0500

Hi,

Should Stephen look at this version in regards to his DISCUSS, or do you 
want to wait for the final one?

Thanks!

Ben.

On 14 Apr 2015, at 9:34, Igoe, Kevin M. wrote:

> I'm being cautious in the generation of test vectors (with 
> intermediate values displayed) becuse , you REALLY
> _______________________________________________
> Audio/Video Transport Core Maintenance
> [email-masked]
> https://www.ietf.org/mailman/listinfo/avt

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From: "Igoe, Kevin M." <[email-masked]>
Date: Thu, 16 Apr 2015 20:03:01 +0000

Nothing substantive that needs Stephen's attention yet.  He'll probably grump 
using a  -8 versus a -64 to denote an 8 byte tag sizes, but that decision was made 
in RFC 5282 long before this ID came along,

> -----Original Message-----
> From: Ben Campbell [mailto:[email-masked]]
> Sent: Thursday, April 16, 2015 3:48 PM
> To: Igoe, Kevin M.
> Cc: [email-masked]
> Subject: Re: [AVTCORE] draft-ietf-avtcore-srtp-aes-gcm-15
> 
> Hi,
> 
> Should Stephen look at this version in regards to his DISCUSS, or do you want to wait for the final one?
> 
> Thanks!
> 
> Ben.
> 
> > A new interim draft draft-ietf-avtcore-srtp-aes-gcm-15 has been
> > posted.  This has (I hope) expunged any references to AES-GCM and
> > reduced to only 3 modes of AES-GCM.  The final draft will include test
> > vectors.
> >
> > intermediate values displayed) becuse , you REALLY don't want any
> > typo's or other errors in test vectors.
> >
> > Audio/Video Transport Core Maintenance [email-masked]

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From: "Ben Campbell" <[email-masked]>
Date: Thu, 16 Apr 2015 15:19:59 -0500

Thanks!